Defrost indicator

ABSTRACT

A defrost indicator having a receptacle configured for containing a quantity of a freezable medium. In some embodiments, the defrost indicator may have an indicator such as an LED light or alarm configured to provide an alert of a defrost condition upon activation, a power source electrically coupled to the indicator, and a disk arranged within the receptacle and configured to activate the indicator. In other embodiments, the defrost indicator may have a pouch containing a frozen indicator tablet comprising a medium having a melting temperature. The medium may include water and a salt in some embodiments.

CROSS-REFERENCE TO RELATED APPLICATIONS

The present disclosure claims priority to Provisional Application No. 62/453,043, entitled “Freezer Defrost Indicator,” and filed Feb. 1, 2017, and to Provisional Application No. 62/508,443, entitled “Freezer Defrost Indicator,” and filed May 19, 2017, the content of each of which is hereby incorporated by reference herein in its entirety.

FIELD OF THE INVENTION

The present disclosure relates to a apparatuses and methods for detecting a defrost condition. Particularly, the present disclosure relates to a defrost indicator for detecting a defrost condition within a freezer or other cooling device or container. More particularly, the present disclosure relates to a freezer defrost indictor for detecting a defrost condition within a freezer or other cooling device or container by providing an alert or visual indication when a freezable medium melts.

BACKGROUND OF THE INVENTION

The background description provided herein is for the purpose of generally presenting the context of the disclosure. Work of the presently named inventors, to the extent it is described in this background section, as well as aspects of the description that may not otherwise qualify as prior art at the time of filing, are neither expressly nor impliedly admitted as prior art against the present disclosure.

Freezers, including commercial freezers and residential freezers for example, are commonly used to store cooked and uncooked foods and other perishable products. Such freezers may be configured to maintain an internal temperature or temperature range, thus maintaining the products stored therein in a frozen state. Such freezers may be powered by various sources, but are typically electrically powered via AC or DC power, for example. If a freezer loses power or experiences a malfunction, the temperature within the freezer may rise. In some cases, products such as various food products, may spoil or risk contamination if the freezer temperature rises or rises above a threshold, even if the temperature increase is only temporary.

Thus, there is a need for a device for providing an indication of a defrost condition in a freezer. More particularly, there is a need for a device for providing a visual and/or audio indication that a freezer is experiencing or has experienced a temperature increase causing a defrost condition.

BRIEF SUMMARY OF THE INVENTION

The following presents a simplified summary of one or more embodiments of the present disclosure in order to provide a basic understanding of such embodiments. This summary is not an extensive overview of all contemplated embodiments, and is intended to neither identify key or critical elements of all embodiments, nor delineate the scope of any or all embodiments.

The present disclosure, in one embodiment, relates to a defrost indicator having a receptacle configured for containing a quantity of a freezable medium, an indicator configured to provide an alert of a defrost condition upon activation, a power source electrically coupled to the indicator, and a disk arranged within the receptacle and configured to activate the indicator. In some embodiments, the indicator may be an LED light or an alarm. The indicator may be electrically coupled to the power source via an electrically conductive material. Moreover, the disk may include an electrically conductive material.

The present disclosure, in another embodiment, relates to a method for detecting a defrost condition. The method may include filling a receptacle with a quantity of a freezable medium, the receptacle having an indicator for providing an alert of a defrost condition. The method may additionally include freezing the freezable medium, arranging a disk within the receptacle, and arranging the receptacle within a cold environment. When a temperature within the environment rises to a predetermined threshold, the freezable medium may melt, causing the disk to activate the indicator.

The present disclosure, in another embodiment, relates to a defrost indicator having a pouch with a pocket formed between two sheets of material, and a freezable medium contained within the pocket. The freezable medium may be a frozen tablet. The pouch material may include low-density polyethylene in some embodiments. In some embodiments, the freezable medium may include a solvent and a solute. The solvent may be water, for example. The solute may include at least one mineral salt, ionic salt, and/or inorganic salt. In some embodiments, the salt may be lithium chloride, sodium chloride, potassium chloride, rubidium chloride, caesium chloride, or francium chloride. In some embodiments, the freezable medium may further include a coloring agent.

The present disclosure, in another embodiment, relates to a defrost indicator having a first indicator tablet formed of a freezable medium having a first melting temperature, the first indicator tablet arranged within a first sealed pouch, and a second indicator tablet formed of a freezable medium having a second melting temperature, the second indictor tablet arranged within a second sealed pouch. In some embodiments, the first and second pouches may be coupled together.

While multiple embodiments are disclosed, still other embodiments of the present disclosure will become apparent to those skilled in the art from the following detailed description, which shows and describes illustrative embodiments of the invention. As will be realized, the various embodiments of the present disclosure are capable of modifications in various obvious aspects, all without departing from the spirit and scope of the present disclosure. Accordingly, the drawings and detailed description are to be regarded as illustrative in nature and not restrictive.

BRIEF DESCRIPTION OF THE DRAWINGS

While the specification concludes with claims particularly pointing out and distinctly claiming the subject matter that is regarded as forming the various embodiments of the present disclosure, it is believed that the invention will be better understood from the following description taken in conjunction with the accompanying Figures, in which:

FIG. 1 is a perspective view of a defrost indicator, according to one or more embodiments.

FIG. 2 is another perspective view of the defrost indicator of FIG. 1, according to one or more embodiments.

FIG. 3 is an internal overhead view of the defrost indicator of FIG. 1, according to one or more embodiments.

FIG. 4 is a cross-sectional view of another defrost indicator, according to one or more embodiments.

FIG. 5 is a perspective view of the defrost indicator of FIG. 4, according to one or more embodiments.

FIG. 6A is a top view of another defrost indicator, according to one or more embodiments.

FIG. 6B is a side view of the defrost indicator of FIG. 6A, according to one or more embodiments.

FIG. 7 is a top view of another defrost indicator, according to one or more embodiments

FIG. 8 is a side view of another defrost indicator, according to one or more embodiments.

DETAILED DESCRIPTION

The present disclosure relates to novel and advantageous defrost indicators. Particularly, the present disclosure relates to novel and advantageous defrost indicators that provide an audio and/or visual indicator that a freezer has experienced a defrost condition. In general, a defrost indicator of the present disclosure may have a receptacle for receiving water, or another liquid or medium that solidifies, gels, or otherwise changes phase at a predetermined or known temperature. In some embodiments, the defrost indicator may be configured as a relatively inexpensive and/or disposable pouch containing a medium in the form of a frozen tablet. The tablet in the pouch may provide a visual indication of a thaw condition. In other embodiments, the defrost indicator may be a vial, cylinder, or other receptacle containing a freezable medium that solidifies, gels, or otherwise changes phase at a predetermined or known temperature. In some embodiments, the defrost indicator may have one or more indicators in addition to a visual indication provided by the medium itself. For example, some defrost indicators may have a light, alarm, and/or other visual or audio indicator electrically coupled to a power source, such as a battery. The defrost indicator may additionally include a disk, ring, or other component moveable within the receptacle and configured to activate the light, alarm, and/or other visual or audio indicator upon reaching the indicator(s). The disk, ring, or other moveable component may have a density greater than that of the medium within the receptacle. For example, in some embodiments, the defrost indicator may be filled or partially filled with water and placed in a freezer or other cooling device, container, or cold environment. Once the water freezes or substantially freezes into ice, the disk, ring, or other moveable component may be arranged above or on top of the ice. If the freezer or other environment experiences a defrost condition due to a loss in power or malfunction, for example, the ice may begin to melt, causing the disk, ring, or other moveable component to sink within the receptacle. The disk, ring, or other component may activate the light, alarm, or other indicator by completing a circuit when it reaches a low point within the receptacle, for example. Defrost indicators of the present disclosure may be used to indicate a defrost condition in freezers, shipping containers or boxes, refrigerated vehicles, or other powered or unpowered devices or environments configured to provide or maintain a frozen environment or a relatively low temperature environment.

A defrost indicator 100, according to at least one embodiment, is shown in FIGS. 1 and 2. The defrost indicator 100 may generally have a receptacle 110 configured to receive a liquid or other medium that solidifies, gels, or otherwise changes phase at a predetermined or known temperature at or above the temperature or temperature range within the freezer or other environment it is intended or configured to be placed in. The receptacle 110 may additionally be configured to receive a disk 120, ring, washer, or other device that is free to move within the receptacle. Indicators such as a light 130 and/or an alarm 132 may be arranged on, in, or otherwise coupled to the receptacle 110. A battery 134 or other power source may be configured to couple to the light 130 and/or alarm 132. Additionally, one or more coupling mechanisms 140, such as one or more suction cups, clips, a hanger, or any other suitable mechanism for temporary or permanent coupling or attachment, may be arranged on an outer surface of the receptacle 110 so as to couple the receptacle to an inner surface or other location of a freezer or other environment.

The receptacle 110 may be configured to receive water, another liquid, or another medium. The receptacle 110 may additionally be configured to contain the liquid or medium as it changes phase. For example, the receptacle 110 may be configured to hold water, and continue containing the water as it freezes into ice. The receptacle 110 may generally have a cylindrical shape in some embodiments, having a circular cross sectional shape. In other embodiments, the receptacle 110 may have a rectangular, triangular, or other suitable shape. The receptacle 110 may have a first end 114, which may be a lower end or bottom end in some embodiments. The first end 114 may be an enclosed end and may be configured to be arranged vertically beneath a liquid or other medium contained within the receptacle 110. The receptacle may additionally have a second end 112, which may be an upper or top end in some embodiments. The second end 112 may be arranged opposite the first end 114. The second end 112 may be an open end or may be configured to be at least partially open so as to receive the water or other liquid or medium contained within the receptacle 110. In other embodiments, however, the second end 112 may be an enclosed end.

The receptacle 110 may have any suitable size. In some embodiments, the receptacle may have a height extending between the first and 114 second 112 ends of between approximately 2 inches and approximately 24 inches. Particularly, the receptacle 110 may have a height of between approximately 4 inches and 18 inches. More particularly, the receptacle 110 may have a height of between approximately 6 inches and approximately 12 inches. In still further embodiments, the receptacle 110 may have any other suitable height extending between the first 114 and second 112 ends. The receptacle 110 may additionally have any suitable diameter or width. In some embodiments, the receptacle 110 may have a diameter or width of between approximately 0.25 inches and 12 inches. Particularly, the receptacle 110 may have a diameter or width of between approximately 0.5 inches and 6 inches. More particularly, the receptacle 110 may have a diameter or width of between approximately 1 inch and 4 inches. In other embodiments, the receptacle 110 may have any other suitable diameter or width.

The receptacle 110 may be composed of any suitable material or materials. In some embodiments, the receptacle may be constructed of one or more plastics, such as a polyvinyl chloride (PVC) plastic. For example, the cylinder may include a hollow PVC pipe in some embodiments. In other embodiments, the cylinder may be constructed of one or more rubber, silicone, metal, glass, and/or other suitable material.

In some embodiments, the receptacle 110 may have one or more transparent or partially transparent surfaces or sides. For example, in some embodiments, the receptacle 110 may have a viewing window comprising a clear or transparent material, such that a user may view the inside of the receptacle. The viewing window may generally extend any suitable distance between the first end 114 and second end 112, and may have any suitable size. In other embodiments, the portion of the receptacle 110 extending between the first end 114 and second end 112 may be entirely or substantially clear, transparent, or partially transparent.

The disk 120, ring, washer, or other device may be configured to be placed within the receptacle 110. The disk 120 may have any suitable size and shape and may be configured to be positioned within the receptacle 110 at any suitable position along a length or height of the receptacle. In this way, the disk 120 may have a size and shape similar to a cross sectional shape of the receptacle 110. For example, in some embodiments, where the receptacle 110 has a cylindrical shape and thus a circular cross sectional shape, the disk 120 may have a circumference with a generally circular shape. The disk 120 may have a hollow ring or washer shape, or may be an enclosed disk or circle, for example. The circular disk 120 may have an outer diameter about the same as, or smaller than, an inner diameter of the receptacle 110. In this way, the disk 120 may be configured to be arranged within the receptacle 110 at generally any position along the length or height of the receptacle. In other embodiments, where the receptacle 110 has a different shape, such as a rectangular prism shape with a rectangular cross sectional shape, the disk 120 may have a rectangular shape generally configured to be arranged within the receptacle. In some embodiments, the disk 120 may have a diameter or width similar to or slightly smaller than an internal diameter or width of the receptacle so as to help maintain the disk 120 in a relatively same orientation as the disk moves along the length of the receptacle. That is, the disk 120 may be sized such that there is a relatively small amount of space between the disk and an inner diameter or width of the receptacle 110, so as to help mitigate flipping or rotating of the disk in the receptacle.

The disk 120 may be constructed of any suitable material(s). In some embodiments, the disk 120 may be constructed of a material configured to sink within the water or other material within the receptacle 110. That is, the disk 120 may be configured to have a density greater than that of the material within the receptacle when above freezing. Additionally, the disk 120 may be constructed of, or may include, an electrically conductive material in some embodiments. For example, the disk 120 may be a copper disk in some embodiments. In other embodiments, the disk 120 may have one or more partially or entirely copper-coated surfaces, for example. In other embodiments, other electrically conductive materials may be used additionally or alternatively.

As described above, the receptacle 110 may have a light 130 and/or alarm 132. The light 130 may be an LED light or other suitable type of light. In some embodiments, the light 130 may be arranged at or near the first end 114 of the receptacle 110. The light 130 may be arranged such that it may be visible when viewing an outer surface of the receptacle 110. The alarm 132 may be configured to provide an audible sound when activated. The alarm 132 may be arranged at or near the first end 114 of the receptacle 110. However, either or both the light 130 or alarm 132 may be arranged at any suitable location along the receptacle 110 that is visible or audible, respectively, to a user. In some embodiments, the receptacle 110 may have additional or alternative visual, audio, or other indicators.

The light 130 and/or alarm 132 may be electrically coupled to the battery 134. The battery 134 may be any suitable battery, such as for example, a lithium battery. The battery 134 may have any suitable size. In some embodiments, the battery 134 may have a standard size and may be configured to be easily removable and replaceable. In other embodiments, the battery 134 may be a rechargeable battery. In some embodiments, the light 130, alarm 132, and/or battery 134 may be electrically coupled via a partial circuit. For example, leads from the light 130, alarm 132, and/or battery 134 may be arranged in communication with a copper trace or another electrically conductive trace or surface. In some embodiments, the first end 114 of the receptacle 110 may have one or more copper traces 136 or other conductive components arranged thereon or incorporated therewith. As shown for example in FIG. 3, one or more copper traces 136 or other electrically conductive components may be arranged on an inner surface of the first end 114. Alternatively, in some embodiments, the inner surface of the first end 114 may be patterned with another electrically conductive material. The traces 136 or other conductive components may be arranged on or near the first end 114 such that the disk 120 may be configured to contact the traces or components when the disk reaches or nears the first end, thereby completing an electric circuit between the battery 134 and light 130 and/or alarm 132.

Another defrost indicator 200 of the present disclosure is shown in FIGS. 4 and 5. Similar to the defrost indicator 100, the defrost indicator 200 may generally have a receptacle 210 configured to receive an amount of water or another liquid or medium. The receptacle 210 may have a height or length extending between a first end 214 and a second end 212. As shown in FIG. 5, the receptacle 210 may have a transparent or substantially transparent viewing window 216 in some embodiments. Additionally or alternatively, the receptacle 210 may have a light 230 and/or other visual or audible indicator. As shown in FIG. 4, the receptacle 210 may additionally be configured to receive a disk 220, ring, washer, or other device configured to indicate a defrost level within the receptacle. One or more attachment mechanisms 240 such as suction cups, clips, or other mechanisms may be arranged on the receptacle 210 for coupling the defrost indicator 200 to an internal wall or other component of a freezer or other environment.

In use, a defrost indicator 100/200 of the present disclosure may provide a visual and/or audible indication that a temperature within a freezer or other environment has increased above a desired threshold temperature. In some embodiments, a user may add water, for example, or another liquid or medium to the receptacle 110/210. For example, a user may add a quantity of water to the receptacle 110/210, typically without completely filling the receptacle, so as to allow room for the water to expand as it freezes into ice. In other embodiments, the receptacle 110/210 may be pre-filled with a predetermined quantity of water or other liquid or medium. The quantity may be predetermined based on allowing the medium room to expand upon freezing, for example. Once the receptacle 110/210 has a quantity of water or another material, the defrost indicator 100/200 may be placed inside a freezer or may otherwise be subject to low temperatures in order to freeze the water or other material, or to otherwise change the phase of the medium contained within the receptacle. Once the material in the receptacle 110/210 reaches or nears freezing, the disk 120/220 may be arranged within the receptacle. For example, where the material is water, once the material, or at least a majority of the material, freezes into ice, a user may place the disk 120/220 on or over the ice. The defrost indicator 100/200 may be placed within a freezer, such as within an interior of the freezer, or within another environment with freezing temperatures. In some embodiments, the one or more attachment mechanisms 140/240 may couple the defrost indicator 100/200 to an interior wall, shelf, rack, or other portion of the freezer or other environment. The indicator 100/200 may remain positioned within the freezer or other environment to provide an indication of defrost or a rise in temperature.

If the freezer or other environment experiences a loss of power or other malfunction causing the internal temperature to rise, the ice or other material within the receptacle 110/210 may begin to melt, or otherwise change phase. As the ice melts, the disk 120/220 may begin to sink below the surface of the material due to its greater density, as described above. If all or substantially all of the ice melts, the disk 120/220 may reach the first end 114/214 of the receptacle, 110/210 at which point the disk may operate to complete the circuit between the battery 134 and the light 130/230 and/or alarm 132. For example, in some embodiments, the circuit may be completed when a copper or other electrically conductive material of the disk 120/220 contacts one or more copper traces 136 electrically coupled to the light 130/230, alarm 132, and/or battery 134. Completion of the circuit at the first end 114/214 of the receptacle 110/210 may activate the light 130/230, alarm 132, or other audio or visual indicator, as described above, thus indicating that the freezer or other environment has experienced an increased temperature.

If power is restored, the malfunction is repaired, or the freezer or other environment otherwise refreezes after experiencing a rise in temperature, the disk 120/220 may remain at or near the first end 114/214 of the receptacle 110/210 as the water or other material inside the receptacle refreezes around the disk, providing a further indication that a defrost condition occurred, in the case of embodiments without a light or alarm or where the light and/or alarm do not remain activated or the battery has died. Moreover, if power is restored, the malfunction is repaired, or the freezer or other environment otherwise refreezes before the disk 120/220 reaches or sinks down to the first end 114/214 (i.e., if only a portion of the water in the receptacle 110/210 has melted prior to refreezing), the disk may remain suspended beneath the surface of the ice/water. In this way, the position of the disk 120/220 within the receptacle 110/210 may provide a visual indicator that the temperature within the freezer or other environment increased at least temporarily and for a long enough period of time to experience a defrost condition. As described above, at least a portion of the receptacle 110/210 wall may be transparent such that a user may be able to locate the disk 120/220 within the receptacle.

According to some additional embodiments, a defrost indicator of the present disclosure may have a relatively small size and may thus be configured for use in a relatively small space. In some embodiments, this relatively small defrost indicator may be configured for use in a cooler, ice chest, personal freezer, shipping box, or other relatively small environment, for example. As with other embodiments, the relatively small defrost indicator may provide an indication that a defrost condition has occurred, or that a temperature has risen above a desired temperature.

For example, in some embodiments, the receptacle for a defrost indicator may be a relatively small vial or tube, such as the vial 800 shown in FIG. 8. The vial 800 may have a length of between approximately 0.5 inches and approximately 6 inches, and particularly between approximately 0.5 inches and 3 inches, in some embodiments. The vial 800 may be composed of glass, plastic, or other suitable materials, as described elsewhere herein. Moreover, the vial 800 may be transparent, translucent, or may have one or more transparent or translucent windows or portions, such that contents of the vial may be viewable. The vial 800 may be filled or partially filled with water, cyclohexane, or another liquid or other medium, as described elsewhere herein. In some embodiments, the medium may be a liquid at generally normal or typical room temperature(s) and may be configured to freeze into a solid or otherwise change phase at a particular temperature, for example. Various indicators may be used to provide an indication of a defrost condition. For example, in some embodiments, a coloring component 802, such as food coloring or another component having a coloring agent, may be arranged in the vial 800.

The coloring component 802 may be a fluid, gel, or solid, for example, and in some embodiments may also be configured to change phase below a particular temperature. The coloring component 800 may include any color or colors of coloring agents, such as blue, red, yellow, or any other suitable color(s). The coloring component 800 may be configured to blend with the medium when the temperature of the medium and/or the temperature of the coloring component rises above the particular temperature. For example, in some embodiments, the medium may be water or another liquid, and the coloring component 802 may be a quantity of water or another liquid combined with food coloring. In other embodiments, the coloring component 800 may be, for example, a powder, compressed powder, tablet, or capsule. The coloring component 802 may be arranged within, above, below, or otherwise proximate to the medium. The coloring component 802 may further be arranged such that, when a defrost condition occurs, the coloring component may contact the medium so as to distribute color within the medium. That is, when the medium and, in some embodiments the coloring component 802, rise above a particular temperature, the coloring component may combine or mix with the medium, and effectively color the medium, or at least indicate a bleeding of color into the medium.

By causing the color of the coloring component 802 to mix with the medium, the coloring component may thus provide a visual indication that a defrost condition has occurred. In some embodiments, the vial 800 may include a plurality of coloring components arranged and configured to indicate different defrost conditions. For example, a first coloring component 802 may be configured to mix with the medium when the defrost indicator raises above a first temperature and/or remains above the first temperature for a period of time, and a second coloring component 804 may be configured to mix with the medium when the defrost indicator raises above a second temperature and/or remains above the second temperature for a period of time. Further, a third coloring component 806 may be configured to mix with the medium hen the defrost indicator raises above a third temperature and/or remains above the third temperature for a period of time. In some embodiments, for example, the first coloring component 802 may include a blue coloring agent, and the second coloring component 804 may include a yellow coloring agent, such that when both of the coloring components mix with the medium, the resulting color may be green. The third coloring component 806 may include a red coloring agent, such that when all three coloring components mix with the medium, the resulting color may be brown or black. In this way, different colors in the medium may indicate that different conditions have occurred. In some embodiments, multiple coloring components may have different melting temperatures or temperature ranges, such that the mixing of each coloring component with the medium may indicate different defrost conditions. It is to be appreciated that in some embodiments, coloring components may be provided without a medium, or pre-mixed with a medium. In still other embodiments, other suitable indicator(s) may be used to provide a visual, audible, or other indication that a defrost condition has occurred.

In yet another embodiment, a defrost indicator of the present disclosure, configured for a relatively small space, may have a receptacle formed of a pouch, packet, or bubble-like container having a flexible or rigid exterior. For example, the receptacle may be formed with two sheets of flexible plastic heat-sealed or glued together around their edges, such that a bubble or pocket may be formed therebetween. FIGS. 6A and 6B show one embodiment of a defrost indicator 600 of the present disclosure having a receptacle formed of a pouch 602. As shown, the pouch 602 may have a generally square shape in some embodiments, with four edges 604. In other embodiments, pouch 602 may have a round, rectangular, triangular, or any other suitable shape. The pouch 602 may include a bubble or pocket 606 configured to hold a suitable quantity of water, cyclohexane, or another freezable liquid or other medium, as described elsewhere herein. In some embodiments, the pouch 602 may be constructed of a flexible plastic material, such as low-density polyethylene (LDPE) or another suitable material. In other embodiments, the pouch 602 may be constructed of a rigid plastic material. The pouch 602 may be generally transparent, or may have a transparent side or portion, such that the indicator medium contained therein may be viewed.

In some embodiments, the pouch defrost indicator 600 may include an indicator tablet or pellet 608 provided within the pouch 602. In some embodiments, the tablet 608 may be or include a frozen medium, such as water, cyclohexane, or another organic or inorganic solvent. The medium may additionally include a solute, such as lithium chloride, sodium chloride, potassium chloride, rubidium chloride, caesium chloride, francium chloride, or any other suitable mineral salt, ionic salt, or inorganic salt or other suitable solute. In some embodiments, the medium may have a predetermined or desired melting temperature. For example, the solvent and solute may be combined at a particular ratio or with a particular concentration in order to provide a medium with a predetermined or desired melting point. In some embodiments, the medium may include a coloring component or dye. For example, the medium may include an edible food dye in some embodiments, or any other suitable coloring component. Additionally or alternatively, the medium may include other components or additives. In some embodiments, the indicator medium may be configured to be relatively safe and/or non-toxic. For example, the use of such materials as water, salt, and food-grade coloring agents may provide for a relatively safe medium. In this way, safety concerns may be reduced or mitigated if the medium should leak, for example, in a shipping container or other environment.

In some embodiments, the indicator tablet 608 may have a particular shape. In some embodiments, the indicator tablet 608 may have a shape configured to provide a visual indication of melting, such as for example a square, triangular, star, heart, or other suitable shape. A shape suitable for melting may have one or more corners, for example, such that the corners may begin to deform upon reaching the medium's melting point. Visible deformation of the tablet 608 shape may provide a visual indication of a defrost condition. Particularly, the amount or extent of the deformation may provide a visual indication of how long the indicator tablet 608 was subject to a temperature at or above its melting point. It may be appreciated that some tablet 608 shapes, such as but not limited to star shapes for example, may more readily exhibit deformation upon reaching a melting temperature. In other embodiments, the tablet 608 may have any other suitable shape, such as a round, oval, or other regular or irregular shape.

In some embodiments, a defrost indicator may have multiple pouches. For example, two, three, four, or any other suitable number of bubbles or pouches may be coupled together at their edges. FIG. 7 shows an example of a defrost indicator 700 with three pouches 702 coupled together. The multiple pouches may be configured to provide an indication of different melting points. That is, for example, where a defrost indicator has three pouches, each pouch may contain a different indicator tablet 704, 706, 708 having a different melting temperature. In this way, the defrost indicator 700 may provide an indication of how high the temperature reached, based on which of the three melting points was reached. For example, where the three indicator tablets 704, 706, 708 have low, mid, and high melting points, respectively, the defrost indicator may provide a visual indication as to how high the temperature reached based on which of the three tablets has melted or shows signs of melting or deformation. In some embodiments, the different tablets having different melting points may be differentiated by color. For example, with respect to the defrost indicator 700, a tablet 704 in a first pouch may be blue, a tablet 706 in a second pouch may be yellow, and a tablet 708 in a third pouch may be red. Additionally or alternatively, the tablets having different melting temperatures may be differentiated by shape, size, or markings thereon. In other embodiments, the pouches containing the different tablets may indicate the different melting temperatures of the tablets.

In some embodiments, a defrost indicator of the present disclosure may be provided with an informational or explanatory guide, such as a card or booklet. The informational guide may include information related to the melting temperature of the medium or mediums contained within the defrost indicator. For example, where a defrost indicator has multiple pouches, each containing a tablet with a different melting point, the informational guide may provide an indication as to the melting point of each tablet. The tablets may be identified by color, shape, size, markings on the tablet or pouch, or any other suitable indicator. Additionally or alternatively, the informational guide may provide information regarding how to interpret a state of the tablet(s). That is, the guide may provide information about what a solid tablet means, what a melted tablet means, and what a partially melted or deformed tablet means. The informational guide may provide information as to different states of deformation of the tablet, for example. In other embodiments, the informational guide may provide alternative or additional information.

It may be appreciated that a defrost indicator of the present disclosure may be configured with one or more customized temperature indicators. For example, where a user of the indicator wants to know when a particular temperature is reached, or when a particular range of temperatures is reached, the medium(s) provided in a defrost indicator may be customized with particular melting points to meet the user's needs. For example, one or more salts or other solutes may be used to modify the melting point of a solvent in order to provide a medium with a particular melting temperature. In this way, defrost indicators of the present disclosure may be customized for use with particular food products, biological or medical products, or other products or frozen environments.

It may further be appreciated that a relatively small defrost indicator, such as a pouch indicator may be manufactured relatively inexpensively. For example, with respect to pouch indicators, the materials used to form the pouches may be relatively inexpensive materials. Additionally, the component(s) used to create the medium may be relatively inexpensive materials, such as water, salt, and food coloring. As mentioned above, in some embodiments, pouch indicators may be manufactured in sheets. For example, a plurality of indicator tablets may be evenly positioned in a spaced apart arrangement on a first sheet of material, such as low-density polyethylene (LDPE). A second sheet of material, such as a second sheet of LDPE, may be arranged over the first sheet and the indicator tablets. Heat sealing, glue, or any other suitable bonding material or mechanism may be used to couple the two sheets of material together around each indicator tablet, thereby encasing each tablet in a bubble or pouch of material. In some embodiments, the sheet may be perforated or scored, such that the individual indicator pouches may be easily separated from the sheet. In some embodiments, a sheet of defrost indicator pouches may provide a plurality of indicator tablets having different melting temperatures, such that one or more indicators having desired melting temperatures may be pulled from the sheet for use as needed. In some embodiments, such pouch indicators may be configured to be disposable.

A relatively small defrost indicator, such as that described herein, may help indicate whether a defrost condition has occurred in a relatively small space. For example, where products are shipped in a frozen state, one or more relatively small defrost indicator may be included in the shipping container to provide an indication to the recipient of whether the products experienced a defrost condition during shipping.

A defrost indicator of the present disclosure may help to identify potential safety concerns by indicating that a product has experienced defrost condition, and/or may allow a user to more quickly detect and correct a power loss or freezer malfunction, for example, thus helping to preserve frozen products that may otherwise be lost or unsafe if left in a defrosted state for too long a period of time. For example, where a freezer or other frozen environment defrosts or partially defrosts, even if only temporarily, products such as food products within the environment may be subject to bacterial growth or other contamination. A defrost indicator of the present disclosure may help to alert a user that food products contained within a freezer or other frozen environment may be unsafe to consume. Similarly, a defrost indicator of the present disclosure may be used to identify a defrost condition in freezers or other frozen environments used to store medications, organs or tissue, blood, specimens, other medical or biological products, product formulas, and/or other products or materials. Where a freezer or other frozen environment defrosts partially and/or temporarily and refreezes, it may be otherwise difficult for a user to determine that a defrost condition occurred. Where frozen products are perishable, subject to bacteria growth, or otherwise damageable from a defrost condition, a defrost indicator of the present disclosure may alert the user that the products should be inspected and/or discarded. Moreover, defrost or partial defrost of products can lead to reduced quality of the products in some instances. A defrost indicator of the present disclosure may provide an indication that quality may be reduced due to a temporary and/or partial defrost.

Components of a defrost indicator of the present disclosure may be configured to withstand relatively low temperature environments and/or continued freeze/thaw conditions. That is, materials and components may be configured to withstand and function within environments of below freezing temperatures for an extended period of time, such that the defrost indicator may be placed within a freezer or other environment for long-term use. Moreover, the components and materials may be configured to withstand and function despite repeated freeze/thaw conditions due to repeated power outages or freezer malfunctions, for example. In some embodiments, for example, the receptacle may be constructed of, or may include, a shatter-resistant material, such as a shatter-resistant polyvinyl chloride. Other shatter-resistant, freeze-resistant, or similar materials may be used additionally or alternatively for the various components of a defrost indicator of the present disclosure.

While the above embodiments are generally described with respect to the use of water as the medium for indicating defrost within the receptacle, other liquids, such as but not limited to cyclohexane, or other mediums may be used as well. For example, while water may generally indicate whether the temperature within the freezer or other frozen environment has risen above approximately 32 degrees Fahrenheit (i.e. the freezing point of water), other mediums or combinations of mediums may be used to determine whether a temperature has risen above a different approximate temperature. That is, other liquids or other mediums may have different freezing, melting, or vaporizing temperatures that may provide an indication that a particular temperature has been reached or exceeded, and may be used to customize the defrost indicator for a particular use. Additionally or alternatively, one or more additives may be used to modify the freezing point of the medium or medium used within the defrost indicator. For example, as described above, one or more ionic, inorganic, or mineral salts may be used to alter the freezing point of water. In this way, additive(s) may be used to customize a defrost indicator for a particular use to indicate a temperature increase above a particular temperature.

In some embodiments, a defrost indicator of the present disclosure may be communicably coupled to a wired or wireless network. For example, a defrost indicator of the present disclosure may couple to a Wi-Fi network, Bluetooth network, and/or other network. In this way, a defrost indicator of the present disclosure may be configured to send an alert or notification to a local or remote device over such a network. For example, a defrost indicator may be configured to send an alert or notification to a smartphone or other computing device or personal device to notify, in many cases quickly notify, a user that a defrost condition has occurred within the freezer or other environment. The notification may be triggered as described above, where a disk, ring, or washer may complete or otherwise active a circuit, for example.

As used herein, the terms “substantially” or “generally” refer to the complete or nearly complete extent or degree of an action, characteristic, property, state, structure, item, or result. For example, an object that is “substantially” or “generally” enclosed would mean that the object is either completely enclosed or nearly completely enclosed. The exact allowable degree of deviation from absolute completeness may in some cases depend on the specific context. However, generally speaking, the nearness of completion will be so as to have generally the same overall result as if absolute and total completion were obtained. The use of “substantially” or “generally” is equally applicable when used in a negative connotation to refer to the complete or near complete lack of an action, characteristic, property, state, structure, item, or result. For example, an element, combination, embodiment, or composition that is “substantially free of” or “generally free of” an element may still actually contain such element as long as there is generally no significant effect thereof.

In the foregoing description various embodiments of the present disclosure have been presented for the purpose of illustration and description. They are not intended to be exhaustive or to limit the invention to the precise form disclosed. Obvious modifications or variations are possible in light of the above teachings. The various embodiments were chosen and described to provide the best illustration of the principals of the disclosure and their practical application, and to enable one of ordinary skill in the art to utilize the various embodiments with various modifications as are suited to the particular use contemplated. All such modifications and variations are within the scope of the present disclosure as determined by the appended claims when interpreted in accordance with the breadth they are fairly, legally, and equitably entitled. Moreover, components or features described above with respect to particular embodiments are not limited to those embodiments, and may be combined with components or features described with respect to other embodiments. 

We claim:
 1. A defrost indicator, comprising: a receptacle configured for containing a quantity of a freezable medium; an indicator configured to, upon activation, provide an alert of a defrost condition; a power source electrically coupled to the indicator; and a disk arranged within the receptacle and configured to activate the indicator.
 2. The defrost indicator of claim 1, wherein the indicator is an LED light.
 3. The defrost indicator of claim 1, wherein the indicator is an alarm.
 4. The defrost indicator of claim 1, wherein the indicator is electrically coupled to the power source via an electrically conductive material.
 5. The defrost indicator of claim 1, wherein the disk comprises an electrically conductive material.
 6. A method of detecting a defrost condition in an environment, the method comprising: filling a receptacle with a quantity of a freezable medium, the receptacle having an indicator for providing an alert of a defrost condition; freezing the freezable medium; arranging a disk within the receptacle; and arranging the receptacle within the environment; wherein, when a temperature within the environment rises to a predetermined threshold, the freezable medium melts, causing the disk to activate the indicator.
 7. A defrost indicator, comprising: a pouch having a pocket formed between two sheets of material; and a freezable medium contained within the pocket.
 8. The defrost indicator of claim 7, wherein the freezable medium is frozen in a tablet.
 9. The defrost indictor of claim 8, wherein the material comprises low-density polyethylene.
 10. The defrost indicator of claim 8, wherein the freezable medium comprises a solvent and a solute.
 11. The defrost indicator of claim 10, wherein the solvent is water.
 12. The defrost indicator of claim 11, wherein the solute comprises at least one of a mineral salt, an ionic salt, and an inorganic salt.
 13. The defrost indicator of claim 12, wherein the salt is selected from the group consisting of: lithium chloride, sodium chloride, potassium chloride, rubidium chloride, caesium chloride, and francium chloride.
 14. The defrost indicator of claim 10, wherein the freezable medium further comprises a coloring agent.
 15. The defrost indicator of claim 7, wherein the pouch is a first pouch, the pocket is a first pocket, and the freezable medium is a first freezable medium having a first melting temperature, the defrost indicator further comprising: a second pouch having a second pocket formed between two sheets of material; and a second freezable medium contained within the pocket, the second freezable medium having a second melting temperature.
 16. The defrost indicator of claim 15, wherein the first and second pouches are coupled together.
 17. The defrost indicator of claim 15, wherein each freezable medium comprises at least one of a mineral salt, an ionic salt, and an inorganic salt.
 18. The defrost indicator of claim 17, wherein for each freezable medium, the salt is selected from the group consisting of: lithium chloride, sodium chloride, potassium chloride, rubidium chloride, caesium chloride, and francium chloride.
 19. The defrost indicator of claim 15, wherein each freezable medium further comprises a coloring agent. 